export default {
    mounted(el) {
        let backgroundImage = el.style.backgroundImage;
        el.style.backgroundImage = "";
        // 观察者
        const observer = new IntersectionObserver(([{isIntersecting}]) => {
            if (isIntersecting) {
                el.style.backgroundImage = backgroundImage;
            }
        })
        observer.observe(el)
    }
}
